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Bhattacharya T.,Institute of Science and Technology for Advanced Studies and Research | Banerjee D.K.,Jawaharlal Nehru University
Environmental Monitoring and Assessment | Year: 2010

This study assessed the heavy metal (Cr, Mn, Ni, Cu, Zn, and Pb) uptake and its effect on biochemical parameters in Paspalum distichum, a wetland plant. Sludge collected from Bhalswa waste dump, New Delhi, was used as heavy metal source and dosed in different proportions viz. 20%, 40%, 60%, and 80% to the garden soil. The plants accumulated metals mostly in belowground organs. The metal accumulation followed the order: Cr>Mn>Cu>Zn>Ni>Pb. The range of heavy metal concentration in tissue of belowground organs after 180 days of growth was 1,778.65-4,288.01 ppm Cr, 828.11-1,360 ppm Mn, 236.52-330.07 ppm Ni, 155.79-282.35 ppm Cu, 27.05-91.16 ppm Zn, and 27.09-50.87 ppm Pb. The biochemical parameters viz. chlorophyll and protein contents and peroxidase (POD) activity exhibited no considerable adverse effect indicating the plants' tolerance towards heavy metals. The high POD activity and synthesis of new protein bands at high sludge-dosed plants were also in support of this fact. © Springer Science + Business Media B.V. 2009. Source

Patel M.M.,Sardar Patel University | Dighe A.,Institute of Science and Technology for Advanced Studies and Research
Progress in Organic Coatings | Year: 2012

Fatty acid based self-crosslinking polyurethane urea (PUU) anionomers can find potential applications in coatings field due to enhanced chemical resistance properties. To optimize their performance in coatings, the molecular features that influence the microphase morphology and dynamic mechanical (DM) behavior of polymer films must be understood and exploited. In this work, comprehensive materials characterization of model PUU anionomers films with oxidative-crosslinking microstructure is addressed. For this, linoleic fatty acid based precursor (LPE) was included in polymer backbone which provides reactive sites for autooxidative polymerization. Three series of compositions were prepared with urea content of 8.4%, 13.2% and 18.1% where within each series LPE content has been increasing in same proportion. Different experimental techniques like FTIR, DSC, DMA and mechanical testing were utilized to study the effect of compositional variables on the extent of phase segregation, domain structure and mechanical properties of fully cured polymer samples. The extent soft segment (SS) oxidative crosslinking had marked effect on the microphase morphology and DM properties of materials of lowest urea content. Significant phase mixing was observed with evolvement of single heterogenous phase in the sample with highest LPE content. Samples with 13.2% urea shows less sensitivity toward increased SS crosslinking in their microphase morphology change. Their mechanical and DM properties were observed to be dominated by interlocked hard domains. With higher urea content, such kind of hard segment cohesion results due to greater strength of bidenate H-bonding among urea linkages. While samples with highest % urea, were clearly found to be well microphase separated compared to other two series with highest HS interconnectivity and have marginal effect of extent of SS crosslinking on microphase separation. This study gives an insight about effect of extent of complex oxidative crosslinking on the microphase separation and DM behavior of segmented PUU anionomers based films with different urea content which is useful in designing such materials in coating system with specific surface structure and function. © 2012 Elsevier B.V. All rights reserved. Source

Bhattacharya T.,Institute of Science and Technology for Advanced Studies and Research | Tiwari K.K.,Sophisticated Instrumentation Center for Applied Research and Testing
Journal of Environmental Biology | Year: 2010

The present investigation was undertaken to assess the biodegradation of phenol by native bacteria strains isolated from coke oven processing wastewater. The strains were designated ESDSPB1, ESDSPB2 and ESDSPB3 and examined for colony morphology Gram stain characters and biochemical tests. Phenol degrading performance of all the strains was evaluated initially One of the strains namely ESDSPB2 was found to be highly effective for the removal of phenol, which was used as sole carbon and energy source. From an initial concentration of 200 mg ť it degraded to 79.84±1.23mg I'. In turn the effect of temperature (20 to 45°C), pH (5-10) and glucose concentration (0,0.25 and 0.5%) on the rate of phenol degradation by that particular strain was investigated. Observations revealed that the rate of phenol biodégradation was significantly affected by pH, temperature of incubation and glucose concentration. The optimal conditions for phenol removal were found to be pH of 7 (84.63% removal), temperature, 30°C (76.69% removal) and 0.25% supplemented glucose level (97.88% removal). The main significance of the study is the utilization of native bacterial strains from the waste water itself having potential of bioremediation. © Triveni Enterprises, Lucknow (India). Source

Patel M.R.,Sardar Patel University | Patel R.B.,Sardar Patel University | Parikh J.R.,Sardar Patel University | Patel B.G.,Institute of Science and Technology for Advanced Studies and Research
Journal of Liquid Chromatography and Related Technologies | Year: 2011

A new, simple, and rapid high-performance thin-layer chromatographic method was developed and validated for quantitative determination of Isotretinoin. Isotretinoin was chromatographed on silica gel 60F254 TLC plate using toluene - methanol (9.0+1.0v/v) as the mobile phase. Isotretinoin was quantified by densitometric analysis at 340nm. The method was found to give compact spots for the drug (RF=0.430.01). The linear regression analysis data for the calibration plots showed good linear relationship with r2=0.9995 in the concentration range 100-500ng/spot. The method was validated for precision, recovery, repeatability, and robustness as per the International Conference on Harmonization guidelines. The minimum detectable amount was found to be 13.72ng/spot, whereas the limit of quantitation was found to be 41.58ng/spot. Statistical analysis of the data showed that the method is precise, accurate, reproducible, and selective for the analysis of Isotretinoin. The method was successfully employed for the estimation of equilibrium solubility, quantification of Isotretinoin as a bulk drug, in commercially available preparation and in-house micro-emulsion based gel formulations. Copyright © Taylor & Francis Group, LLC. Source

Aggarwal A.,Gujarat Technological University | Gandhi S.,Gujarat University | Chaubey N.,Institute of Science and Technology for Advanced Studies and Research | Jani K.A.,Ganpat University
International Conference on Advanced Computing and Communication Technologies, ACCT | Year: 2014

Mobile Ad Hoc Networks (MANETs) are collections of mobile nodes that can communicate with one another using multihop wireless links. MANETs are often deployed in the environments, where there is no fixed infrastructure and centralized management. The nodes of mobile ad hoc networks are susceptible to compromise. In such a scenario, designing an efficient, trustworthy and secure routing protocol has been a major challenge over the last many years. In this paper, we propose a Trust Based Secure On Demand Routing Protocol called 'TSDRP' for MANETs. Ad hoc On-demand Distance Vector (AODV) routing protocol has been modified to implement TSDRP for making it secure to thwart attacks like Blackhole attack and DoS attack. To evaluate the performances, we have considered Packet Delivery Fraction (PDF), Average Throughput (AT) and Normalized Routing Load (NRL). © 2014 IEEE. Source

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